This is a 3 part series demonstrating the properties of lead acid batteries. In this video the properties of a battery while discharging are shown. The graphs show that battery state of charge (SoC)is in directly related in a near linear fashion to voltage. A rough calculation is shown as 0.022v per 1% SoC.
It is important to prevent deep discharges of lead acid batteries since the service life can be significantly shortened if discharged below 50% SoC. For normal usage with long service life it is good to assume that the usable capacity is half that of the battery's rating and that the battery is "dead" when it's no load/no charge voltage is ~11.6v. This roughly equates to 50% discharged. If the only display of battery SoC is no load voltage then I find is easier to think of the battery as full at 12.7 and empty at 11.6v. This mindset prevents me from inadvertently discharging past 50%. I roughly consider that ~0.1v = ~10% of usable capacity.
Links to all the videos in this series:
Properties of Lead Acid Batteries #1 - Surface charge - • Properties of Lead Aci...
Properties of Lead Acid Batteries #2 - Discharge Amp-Hours - • Properties of Lead Aci...
Properties of Lead Acid Batteries #3 - Charging Amp-Hours - • Properties of Lead Aci...
The load tester used in this video can be bought at:
www.westmountainradio.com
For a wealth of information regarding batteries check out Battery University. It is free. The link below is one of their many pages. This one discusses surface charge.
batteryuniversity.com/learn/ar...